Like the previous regions in the previous games, Sinnoh features a broad range of environments for the player character to explore. The region is mountainous and temperate, and features, for the first time in a Pokémon RPG, snowy routes. While this region's location with relation to other regions portrayed in the franchise is unknown, Ash Ketchum refers to Sinnoh as an island during the English dub of the last episode of season 9 of the anime, while Professor Oak mentions that it's located to the north of the Kanto/Johto landmass. The in-game map shows that the region consists of about 70% land and 30% water. There are thirty routes in Sinnoh numbered 201 to 230 and, like the Hoenn region before it, do not follow sequentially from the previous region's routes: routes in Hoenn, the previous region, were numbered 101 to 134.

Sinnoh has four lakes, each of which houses a legendary Pokémon: Lake Acuity houses Uxie, Lake Valor houses Azelf, Lake Verity houses Mesprit, and the secret Sendoff Spring houses Giratina inside Turnback Cave. Sinnoh is based on the geography of the Japanese island of Hokkaidō and the disputed island of Kunashir (Kunashiri).

Sinnoh features an extensive underground area called The Underground. In this area a player character can dig for stones, items, and spheres which can be exchanged for items with underground barterers. This is also the place that you can find fossils instead of obtaining one and not being able to collect the other such as in Pokémon Emerald Version. The player character can also use DS Wireless Communication compete with player characters within the area to a game of 'Capture the Flag'.

Contents

Cities and towns

Twinleaf Town

Twinleaf Town (フタバタウン Futaba Taun) is the town in which the protagonists of Diamond and Pearl, the player character and their archrival, reside and from which they begin their journey across the region of Sinnoh, located south of Route 201, southwest of Sandgem Town, southeast of Lake Verity, and north of a small pond.

Jubilife City

Jubilife City (コトブキシティ Kotobuki Shiti) houses a television station, the Trainer's School, "Pokétch Company", the company which makes the Pokétch, and the Global Trade Station or GTS, which allows for trading over the Nintendo Wi-Fi Connection.

Oreburgh City

Oreburgh City (クロガネシティ Kurogane Shiti) is a coal-mining city, home to the first Sinnoh region Gym Leader - Roark. The city is powered by coal and it also houses a museum which revives the fossils of ancient Pokémon.

Floaroma Town

Floaroma Town (ソノオタウン Sonō Taun) is a flower-loving city, where many of the fields have endless amounts of flowers in them — of all colors. Many trainers are attracted to the city because of the fragrant smell. The Pokémon Contests have relevance in this town because of the Pick a Peck of Flowers Shop, where one can purchase Pokémon accessories. There is also a man that sells honey in the flower fields.

Eterna City

Eterna City (ハクタイシティ Hakutai Shiti) is home to the second Gym Leader, Gardenia, as well as a Bicycle Shop and a Team Galactic building. The Underground Man also lives in Eterna, he will give the player character the Exploration Kit, allowing the player character to enter the Underground and he will continue to tutor the player character on the underground.

Veilstone City

Veilstone City (トバリシティ Tobari Shiti) is home to the third Gym Leader, Maylene, as well as a Department Store, Game Corner (which it is very famous for), and Team Galactic's official Regional Headquarters and Warehouse. To the east of Veilstone are boulders which can change the form of the player character's Deoxys. In the anime, it is the hometown of Paul.

Celestic Town

Celestic Town (カンナギタウン Kannagi Taun) is a small town just right next to Eterna City. It is home to an ancient artifact honoring the legendary Pokémon Uxie, Mesprit, Azelf, Dialga, and Palkia. It, like Eterna city, is very traditional and houses many legends.

Pastoria City

Pastoria City (ノモセシティ Nomose Shiti) is home to the fourth Gym Leader, Crasher Wake, as well as the Great Marsh, Diamond and Pearl's equivalent of the Safari Zone. Lake Valor is in between Pastoria. Team Galactic uses the Great Marsh here to test the Galactic Bomb.

Solaceon Town

Solaceon Town (ズイタウン Zui Taun) is home to a Day-care Center. Nearby is the Solaceon Ruins, which contain the Unown.

Canalave City

Canalave City (ミオシティ Mio Shiti) is home to the sixth Gym Leader, Byron. Canalave City also has a port in which the player character can board a ship to Iron Island, an island off Sinnoh. The city also houses the Harbor Inn, which the player character must access to capture Darkrai via an event.

Snowpoint City

Snowpoint City (キッサキシティ Kissaki Shiti) is home to the seventh Gym Leader, Candice, and a temple containing the Legendary PokémonRegigigas. On certain predetermined days, a weather effect called diamond dust occurs. In Pokémon Platinum for the Nintendo DS, this occurs on the users birthday,which is set in the control panel.

Sunyshore City

Sunyshore City (ナギサシティ Nagisa Shiti) is home to the eighth Gym Leader, Volkner, a market for buying seals that can be placed on Poké Balls and a lighthouse that overlooks the Pokémon League. Much of the city is powered by solar cells. Also, the Olivine City Gym Leader, Jasmine, is present by the route to the Pokémon League. The city experiences a crippling blackout until the player character engages Team Galactic and Dialga or Palkia at Spear Pillar.

Pokémon League

The Sinnoh Pokémon League (ポケモンリーグ Pokemon Rīgu) Headquarters is portrayed as a magnificent castle at the top of a large waterfall in Diamond and Pearl.

Places of Interest

Eterna Forest

Eterna Forest is large forest in the Sinnoh region which leads to Eterna City. The player character can meet Cheryl here who will travel with the player character tld o the end and will then give the player character a soothe bell.This forest also houses the Old chateau

Old Chateau

The Old Chateau (もりのようかん Mori no Youkan) in original Japanese language versions}} is a crumbling haunted mansion in Eterna Forest. The player character can acquire Rotom here. There are several ghosts which appear on occasion, although they can not be interacted with. You need to go to the Old Chateau during the night to get Rotom.

Mt. Coronet

The Mt. Coronet is tallest mountain in Sinnoh. It divides Sinnoh in half. Notable features include the Spear Pillar, where the climax of the story occurs. The player character battles Team Galactic Admins and then their Leader. You can catch Palkia or Dialga here. Arceus can be caught if the player character has the Azure Flute.

Solaceon Ruins

The Solaceon Ruins is a cave in Solaceon Town that is home to the Unown. It is also is home to three evolution stones using dowsing app. You can also find HM defog.

Great Marsh

The Great Marsh (だいしつげん Dai Shitsugen) is where the Safari Game is held. The Great Marsh is a large area divided into six smaller areas labelled from one to six. Instead of normal grass, Pokémon in the Great Marsh are found in grassy mud. After the National Dex is obtained several new Pokémon can be found; these include Tropius, Carvanha, Yanma etc.

Pokémon Mansion

The Pokémon Mansion a large mansion with a trophy garden at the back. After the National Dex is obtained several new species of Pokémon can be found in the garden, in order to find them the player character must talk to the owner who will then send out his butler to investigate. you can also fight 5 maids after you defeat them all you can fight a rich boy. On the east side of the mansion a maid is in the way and says "I'm very sorry but you can't go through here."

Iron Island

Iron Island (こうてつじま Kōtetsu-jima) is the training place of the people of Canalave City's Gym and Riley, a trainer who gives the player character a Riolu egg. There is a cabin where Byron lives, and a cave.

Fullmoon Island

Fullmoon Island (まんげつじま Mangetsu-jima) is home to the Legendary Pokémon Cresselia. It runs away after the player character sees it long enough for it to be entered into the Pokédex.

Turnback Cave

Turnback Cave's location

Turnback Cave (もどりのどうくつ Modori no Doukutsu) is at the center of Sendoff Spring, the fourth lake of Sinnoh that was hidden long ago. It leads into an alternate dimension, where Giratina is housed.

Newmoon Island

Newmoon Island (しんげつじま Shingetsu-jima) is home to the Legendary Pokémon Darkrai, but can only be reached with a "Member's Card", or a cheat device.

Flower Paradise

The Flower Paradise (はなのらくえん Hana no Rakuen) is accessed with a special item called "Oak's Letter," which must be obtained through a Nintendo event. Shaymin is available here.

Hall of Origin

The Hall of Origin (はじまりのま Hajimari no Ma) is accessed with a special item called "Azure Flute", which must be obtained through a Nintendo event. The Hall of Origin is located high above Spear Pillar on Mt. Coronet, where the player character battles Dialga or Palkia. Arceus resides in the Hall of Origin.The hall of origin is the highest reachable point in Sinnoh.